Movable panel structure



June 8, 1954 T. M- RUTHERFORD I 2,680,268

MOVABLE PANEL STRUCTURE Filed Nov. 21, 1952 2 Sheets-Sheet l INVENTOR.

' THOMAS M. RUTHERFORD- By J m,

ATTORNEYS.

June 8, 1954 T. M- RUTHERFORD 2,680,268

MOVABLE PANEL STRUCTURE Filed Nov. 21, 1952 2 Sheets-Sheet 2 l a 57 E 3832 27 Z 54 74 g 73:? V 27 \V v I Y? R?" ..-f .3. 31 .6 it 10 7 INVENTOR...THOMAS M. RUTHERFORD.

BY Edam mm wfiw z ATTORNEYS.

Patented June 8, 1954 v UNITED STATES PATENT OFFICE MOVABLE PANELSTRUCTURE Thomas M. Rutherford, Los Angeles, Calif. I ApplicationNovember 21, 1952, Serial No. 321,797

14 Claims. 1

The present invention pertains broadly to the field of sliding doors orpanels; more specifically it presents a sliding door that may be movedlongitudinally as well as laterally, and in detail, it is directedprimarily to a door which when in the closed position appears to be anintegral part of the adjacent wall structure.

Although many sliding door designs have been devised and marketed in thepast, the majority of such structures have the disadvantage that theirparticular location is readily apparent due to the fact that theexterior surface of the door and the wall surface are not in the samevertical plane. The position of most sliding doors of previous design ina wall structure, is immediately ascertainable by the projecting handleor similar accessory employed in moving the door longitudinally. Earlierdoors of this type have been found most unsatisfactory from anarchitectural standpoint in the design of modern homes and buildings,for it is impossible to achieve the long unbroken, streamlined wallareas desired.

A major object of the present invention is to provide a slidable doorthat may be moved both longitudinally and laterally, and one thateliminates the disadvantages of the prior art devices.

Another object of the invention is to supply a sliding door that isparticularly adapted for use as a convenient and easily operated closurefor closets, and one that may be moved to either an open, or closedlongitudinally slidable position by the application of slight pressurethereon.

Yet another object of the invention is to provide a novel looking orholding mechanism for use in conjunction with a longitudinally andlaterally movable panel.

A further object of the present invention is to furnish a sliding doorhaving an extremely simple mechanical structure that may be fabricatedfrom inexpensive standard commercially available materials, and requiresa minimum of maintenance attention.

A still further object of the invention is 'to provide a framework inwhich two independently movable doors or panels may be slidablypositioned for easy access to space behind the framework, with saiddoors or panels providing a continuous surface within a wall structurewhen in the closed position.

These and other objects and advantages of my invention will becomeapparent from the following description of a preferred form, and certainalternate forms thereof, taken in conjunction with the accompanyingdrawings wherein:

Figure 1 is a front perspective view of the sliding door of the presentinvention;

Figure 2 is a rear perspective view of the device;

Figure 3 is a vertical cross-sectional view of the device taken on theline 3-3 of Figure 2;

Figure 4 is a perspective view of one side of the panel-lockingmechanism;

Figure 5 is a perspective view of the locking mechanism shown in Figure4, taken from the reverse side thereof;

Figure 6 is a side elevational view of the looking mechanism holding alaterally movable panel in a position where it may be movedlongitudinally;

Figure 7 is a side elevational view of the looking mechanism being movedinwardly to assume a non-holding position;

Figure 8 is a side elevational view .of the locking mechanism after ithas assumed a nonholding position;

Figure 9 is a side elevational view of the looking mechanism as it ismoving into the position shown in Figure 2;

Figure 10 shows an alternate form of longitudinally and laterallymovable panel and looking mechanism therefor; and

Figure 11 is a perspective view of an alternate form of my invention.

Referring now to Figures 1 and 2 for the general arrangement of apreferred form of the invention, it will be seen that it embodies twovertically disposed panels P and S. Panels P and S are longitudinallymovable within the confines of a framework F. When panel 8- is moved toeither end of framework F, an opening is provided in the framework inwhich the panel P may be moved forwardly to assume a position flush withthe panel S, as will be explained in detail hereinafter. When panel P isin the closing position, it is flush with and in substantially the samevertical plane as panel S. By the application of pressure on panel P, itmay be moved to the frame-closing position shown in Figure 2, or to aninwardly disposed vertical position relative to panel S whereby bothpanels may be moved longitudinally and independently the length of theframework F.

As seen in Figure 1, the framework F includes a horizontally disposedheader I!) that is supported by two longitudinally spaced vertical endpieces II and H from a sill l2. An elongate member l3 of invertedchannel-shaped cross section is disposed in the upper rearward portionof the framework F parallel to header in (Figure 2). The ends of memberl3 abut against the interior faces of end pieces H and may be rigidlyaifixed thereto by conventional fastening means. In practice it has beenfound convenient to support 3 member 13 in the desired position on theupper ends of two vertical uprights l4 and i4 that are rigidly affixedto the interior faces of end pieces H and H respectively.

The cross section of member i3 is such that two upwardly disposed,laterally separated tracks i5 and 16 are provided (Figure 3), joined ontheir lower ends by a web 11- Panel S is substantially rectangular inshape and may be formed from any rigid sheet material such as wood, orthe like. Two L-shaped hangers 18 are vertically disposed inlongitudinally spaced relationship on the upper portion of panel S asshown in Figure 1. Each hanger i8 has a short horizontally disposedshaft 25 extending forwardly from the upper portion thereof, and tworollers 25 are rotatably mounted on the shafts [9. Each roller is formedwith a groove 23a that engages the upper edge of track to movablysupport panel S in a hanging position therefrom.

Panel P, like panel S, is formed from a rectangular rigid sheet, andwhen disposed in a non-closing position, panel P is situatedsubstantially under track 16, but laterally separated from panel S topermit each panel to be moved longitudinally within the confines offramework E.

An open rectangular frame 25 serves to support panel P. Frame 25 may befabricated from a number of different structural materials of a varietyof cross sections. However, it has been found expedient to fabricateframe 25 from two longitudinally spaced, vertical rods 26 of annularcross section, the lower end portions of which are rotatably mounted ina rigid horizontally disposed connector 27 of transverse L-shaped crosssection, with their upper ends rotatably engaging a head member 23,likewise of L-shaped cross section. Head member 28 includes a verticalup wardly extending flange 25 running the entire length thereof, fromwhich two longitudinally spaced horizontal stub shafts 39 extendforwardly. Two grooved rollers 3| are rotatably mounted on shafts 30,with grooved portions 31a of the rollers engaging the upper edge oftrack IE to movably support the frame 25 therefrom.

Connector 2'? includes a vertical downwardly extending flange 32 thatslidably engages a groove 33 formed in sill 12 to maintain frame 25 in afixed vertical plane. Groove 33 extends substantially the entire lengthof sill l2. Each frame rod 26 has two vertically spaced, horizontallydisposed arms 34 extending forwardly therefrom that terminate in eyes34a. Each eye 34a is engaged by a bolt 35, or other elongate fasteningmeans, which also pivotally engages a horizontally disposed arm 36. Arms35 are preferably formed as an integral part of L-shaped brackets 36aaffixed to the rearward surface of panel P by conventional fasteningmeans (Figures 2 and 3).

Thus it will be seen that when so supported, panel P may be moved bothlongitudinally and laterally relative to the framework F. Figures 2 and3 also illustrate the manner which panel P is constantly urged forwardlyfrom the frame 25 by spring means. Although a variety of spring meansmay be employed for this purpose, it is preferred to employ a number ofU-shaped springs 31. Each spring 31 includes two legs 37a and 31b thatare at all times under compression, and engage the rearward surface ofpanel P and a portion of the forwardly disposed surface of one of therods 25. It will be noted that each spring 37 is formed with a loop 310at the apex of the two legs which snugly encircles one of the bolts 35,serving to maintain the spring in a fixed horizontal plane.

The looking or holding mechanism 4i! utilized in maintaining panel P inthe rearwardly disposed position whereby it may be longitudinally movedwithin the confines of framework F, is best seen in Figures 4 and 5.This locking mechanism embodies an L-shaped bracket 38 rigidly affixedto the upper surface of connector 21 by suitable fastening means.Bracket 39 includes a vertical upwardly extending arm Mechanism it alsoembodies a flat substantially rectangular plate ill affixed by means ofscrews 32, or the like, to the rearwardly disposed face of panel 1?forwardly from arm 3%. Lug a is bent substantially normally to plate iiand extends forwardly into a recess formed in panel P, and by a similarbending operation lug Gib is disposed to extend rearwardly from platell, also substantially normal thereto.

An elongate detent 4'63 is pivotally supported on a screw, pin or otherelongate member 44 rigidly mounted in recess 32 normal to lug Ilia, anddetent 53 extends rearwardly to terminate in a point 355 (Figure 3) Thelower rear edge of detent 43 includes a curved portion tide whichextends downwardly and forwardly from point 45 to develop into avertical seat lfi. Seat 45 is adapted for removable engagement with theupper end portion of arm 39 to maintain panel P in the rearwardlydisposed and longitudinally movable position shown in Figure 2. Panel Pis moved to the rearward position by simply applying rearwardly directedpressure to the forward surface thereof when the panel is in the closedposition.

A release member l! functions to free detent 43 when it is in engagementwith arm 39. Release member al is in the form of an L-shaped plate andis pivotally supported near its apex by a pin or screw d9 mounted ondetent 33 as shown in Figures 4 and 5. Member l? has a curved concavelower edge 53 disposed above the lower edges l3a and seat 46 of detentd3 when panel P is in the frame-closing position shown in Figure 2. Alip 51 is formed on the outer edge of release member 41 and has aforwardly disposed face that is engaged by the point 35 when the detentis in the position shown in Figure 2. Lip 5i not only shields the pointbut prevents downward movement of detent :33 below a predeterminedelevation, as will be explained hereinafter. A downwardly and rearwardlyextending first link 52 is formed on the forwardly disposed portion ofrelease member M. A second upwardly and rearwardly extending link 53 ispivotally supported by a pin or screw 56 that extends through a boreformed in the lower end portion thereof and a bore formed in lug 5 lb.

The outer end portions of links 52 and 53 overlap, and each is formedwith a bore through which a pin or screw 55 depends to rotatably supporta roller 56. A helical spring 5'1 that is at all times under tensionextends between pins 5% and 33, with the spring at all times tending torotate the detent 43 downwardly. However, when detent point .55 and lip51 contact one another, downward movement of detent 43 is limitedthereby.

When it is desired to cause panel P to move from the rearward positionto the forward frameclosing position, rearwardly directed pressure ismomentarily applied to the panel, whereupon panel P moves rearwardly andthe roller 58 is brought into contact with the forwardly disposed faceof arm 39, as shown in Figure 7. Further rearward movement of panel Pcauses links 52 and 53 to pivot forwardly relative to one another, andassume the angular slightly forwardly extending position shown in Figure10. With links 52 and 53 so disposed, the detent 43 has been pivoted toa position where seat 49 thereof is disposed above the upper edge of arm39. Upon release of pressure, panel P will automatically move forwardlyto a frame-closing position due to the compression on the U -shapedsprings 3'1. A rearwardly disposed portion 59a of the lower edge ofrelease member 41 is situated below the level of the upper edge 39a ofarm 39, and slidably contacts same after the panel P has moved forwardlya sufficient distance that seat 46 cannot engage arm 39 when the detentpivots downwardly.

As panel P moves forwardly the release member 41 pivots upwardly and thelinks 52 and 53 rearwardly. When links 52 and 53 have pivoted rearwardlybeyond a position where they are in coaxial alignment as shown in Figure9, spring 51 tends to move them toward one another and at the same timemove detent 43 downwardly until it reaches the position shown in Figure2. When panel P is closed as just described, the detent 43 is sodisposed that it may readily engage arm 39 to hold the panel P in alongitudinally movable position relative to the framework F.

Panel P is moved from the closed position to the rearwardly disposedposition shown in Figures l and 2, by simply applying rearwardlydirected force thereto to cause the lower rearward edge 93a of thedetent to engage the upper edge 39a of arm 39, raising the detent to theposition shown in Figure 6 where the seat 46 engages the 5 arm 39 due tothe action of helical spring 51. When it is desired to return panel Pfrom this rearwardly disposed position to a frame-closing position, thepreviously described operation is repeated.

In Figure an alternate form of the invention is shown in which a tubularconstruction is employed. Two laterally spaced, downwardly extendingJ-shaped track members 69 and 5! are provided which are connected ontheir upper ends by a web 62 to form an integral member 63. However,should it be desired, member 63 may be supported from the vertical endpieces forming a part of framework F, or from uprights afiixed theretoas in framework F.

A panel S identical to panel S, has a number of longitudinally spacedhangers 64 mounted on the upper portion thereof. Each hanger has a shortstub shaft 65 extending forwardly therefrom on which a grooved roller 99is rotatably mounted. Rollers 66 engage the edge 59a of track member 59,to permit panel S to be movably supported therefrom.

A rectangularly shaped frame 6'! for the support of panel P isfabricated from two vertical, laterally spaced tubes 68 that are joinedon their upper ends by a head member 69 of L-shaped cross section, andon their lower ends by a connector 19 of similar cross section. Eachtube 98 has a second tube 68a rotatably mounted thereon with the secondtube being maintained at the desired elevation by a bearing assembly 7|.Bearing assembly H is preferably of the roller or ball bearing type,with one portion 12 thereof rig-idly affixed to tube 58 and the other totube GM, as best seen in Figure 10. A downwardly extending threadedmember I3 having a slot 13a formed in the lower end thereof is providedfor each tube 68 and engages the lower end thereof. By properorientation of members 13, the slots (3a are disposed parallel toconnector l0, and slidably engage a rail 14 afiixed to sill l2 of theframe F.

Two vertically spaced, horizontally disposed arms 15 are affixed to eachtube 68a and extend forwardly therefrom. An eye bolt 16 extendsforwardly from and is supported by each arm 15. Should it be desired,the eye bolt 16 and arm 15 may be formed as an integral unit. Each eyebolt pivotally engages a, vertically disposed pin or bolt 11 which inturn engages a suitable bracket 18 rigidly mounted on the rearwardlydisposed face of panel P.

A locking mechanism 49 is provided for the alternate form of theinvention and operates precisely in the same manner employed in thepreferred form previously described.

The use and operation of both the preferred and alternate forms of thesliding door of the present invention are extremely simple. When it isdesired to place panel P or P in a frameclosing position, the panel S orS is moved to one end of the framework. The panel P or P is then movedto the opposite end of the framework, and slight inward pressure appliedthereto will cause the locking mechanism 49 or 40 to move from theposition shown in Figure 6 to that of Figure 2. No forward force need beexerted on panel P or P to bring it into a frame-closing position, asthis is accomplished by springs 31.

When it is desired to place panel P or P in a rearwardly disposedposition where it may be moved longitudinally in framework F or F aslight pressure is exerted on the exterior face thereof. This inwardpressure causes rearward movement of the panel as the mechanism 40 or40' changes from the looking to the non-locking position. In Figure 2 astop 89 is shown, which may be used in either form of the invention tolimit longitudinal movement of frame 25. Stop 89 may be so disposed thatpanel P or P will completely fill the opening in framework F or F whenit moves forwardly into flush vertical alignment with panel S or S aspreviously explained.

An alternate form of my invention is shown in Figure 11. A rectangularframe 90 is provided, and is preferably fabricated from two spacedvertically disposed end pieces 9| and 9| that are of channel shapedcross sections. The end pieces 9! and 9| are rigidly connected by aheader 92 and base member 93, which are also of channel shaped crosssection. A sheet of material 94 such as plywood is rigidly aflixed tothe exterior portion of frame 99, and is of the same exteriordimensions. The frame 90 and sheet 94 cooperate to provide a panel P".

Two vertical rods 95 and 95' are provided, and are pivotally supportedby header 92 and base member 93. The rods 95 and 95' are disposed withinthe confines of end pieces 9| and 9i respectively. Rod 95 has tworearwardly extending arms 96 and 91 mounted on the ends thereof, and rod95 is similarly provided with arms 96 and 91'.

The rearwardly disposed ends of 96 and 9B are pivotally connected bypins 98 to a first horizontally disposed member 99 of L-shaped crosssection. A second horizontally disposed member I99 has the ends of arms91 and 9lpivotally connected thereto by pins I 0|.

Member 99 is of L-shaped cross section and has an upwardly extending leg99a from which two longitudinally spaced horizontal shafts I02 extendrearwardly to rotatably support two grooved rollers I83. The rollers Hi3movably engage a rail (not shown) to support my invention therefrom. Thesecond member Hill is also of L-shaped cross section and has adownwardly extending leg [00d that slidably engages a slot or guidemeans (not shown) to maintain members 99 and H10 in vertical alignment.

This alternate form of my invention operates in the same manner as theform of my invention shown in Figures 1 and 2. The form of my inventionshown in Figure 11 has the advantage, that is important in someinstallations, that no end pieces extend between the members 99 and H30.

Although the sliding door structures above described are fully capableof achieving the objects and providing the advantages hereinbeforementioned, it is to be understood that they are merely the presentlypreferred embodiments of the present invention and that it is not meantto limit the particular construction herein shown and described otherthan as defined by the ap pended claims.

I claim:

1. A movable panel structure which includes: a substantially rectangularpanel; a substantially rectangular member parallel to said panel; meansmovably supporting said panel from said member that at all timesmaintain said panel parallel thereto; spring means that constantly urgesaid panel forwardly from said member; means preventing said springmeans from moving said panel forwardly beyond a first vertical plane;locking means operatively associated with said panel and member thatremovably maintains said panel in a second plane when sufficientpressure is applied to said panel to move it thereto, said locking meansreleasing said panel from said second plane when said panel is movedrearwardly therefrom by application of pressure, and said spring meansmoving said panel forwardly from said second to said first plane afterthe pressure on said panel is removed; and means to movably support saidmember in a fixed vertical plane.

2. A movable panel structure which includes: a panel; a rigid framedisposed parallel to said panel; a plurality of arms pivotallysupporting said panel from said frame; roller means mounted on saidframe to movably support said frame on a track; guide means mounted onsaid frame to maintain said frame in a fixed vertical plane when saidframe is supported on said track; spring means for urging said panellaterally away from said frame to a first vertical plane relative tosaid frame; and locking means operatively associated with said panel andframe removably holding said panel in a second vertical plane relativeto said frame when sufficient pressure is applied to said panel to causeit to move to said second plane, and which releases said panel from saidsecond plane when further pressure is applied to said panel permittingsaid spring means to return said panel to said first vertical plane.

3. A movable panel structure which includes: a panel; a frame disposedparallel to said panel; means that movably support said panel from saidframe and at all times maintain said panel parallel thereto; springmeans that constantly urges said panel orwardly from frame; means thatprevent said spring means from moving said panel forwardly beyond afirst vertical plane; locking means operatively associated with saidpanel and frame that maintains said panel in a second vertical planewhen sumcient pressure is applied to said panel causing it to move tosaid second plane; a horizontally disposed track; roller means mountedon said frame engaging said track; and guide means operativelyassociated with said frame that cooperate with said roller and track tomaintain said frame in a fixed vertical plane.

4. A movable panel structure which includes: a substantially rectangularpanel; a substantially rectangular frame parallel to said panel; meansthat movably support said panel from said frame and at all timesmaintain said panel parallel thereto; spring means that constantly urgesaid panel forwardly from said frame; means that prevent said springmeans from moving said panel forwardly beyond a first vertical plane;spring-actuated locking means associated with said panel and frame thatremovably maintain said panel in a second vertical plane when sufficientpressure is applied to said panel to cause it to move thereto; a releasemember operatively associated with said locking means that releases saidpanel from said second plane when pressure is applied to said panel tomove it rearwardly therebeyond, said spring means moving said panelforwardly from said second plane to said first plane after the pressureon said panel is removed; and means to movably support said frame in afixed vertical plane.

5. A movable panel structure which includes: a substantially rectangularpanel; a substantially rectangular frame parallel to said panel; meansthat movably support said panel from said frame and at all timesmaintain said panel parallel thereto; spring means that constantly urgesaid panel forwardly from said. frame; means that prevent said springmeans from moving said panel forwardly beyond a first vertical plane;springactuated locking means associated with said panel and frame thatremovably maintain said panel in a second vertical plane when sumcientpressure is applied to said panel to cause it to move thereto; a releasemember operatively associated. with said locking means that releasessaid panel from said second plane position when pressure is applied tosaid panel to move it rearwardly therebeyond, said spring means movingsaid panel forwardly from said second position to said first positionafter pressure on said panel is removed; a horizontally disposed track;roller means mounted on said frame engaging said track; and guide meansoperatively associated with said frame that cooperate with said rollerand track to maintain said frame in a fixed vertical plane.

6. A movable panel structure which includes: a substantially rectangularpanel; a substantially rectangular frame parallel to said panel; meansthat movably support said panel from said frame and at all timesmaintain said panel parallel thereto; spring means that constantly urgesaid panel forwardly from said frame; means that prevent said springmeans from moving said panel forwardly beyond a first vertical plane; aspringloaded locking member pivotally supported from said panel capableof removably engaging a portion of said frame to hold said panel in asecond vertical plane when sufi'icient pressure is applied to said panelcausing it to move thereto; a release member operatively associated withsaid locking member that releases said panel from said second planeposition when pressure is applied to said panel to move it rearwardlytherebeyond, and said spring means moving said panel forwardly from saidreleased position when pressure on said panel is removed; and means tomovably support said frame in a fixed. vertical position.

'7. A movable panel structure which includes: a substantiallyrectangular panel; a substantially rectangular frame disposed parallelto said panel; means that movably support said panel from said frame andat all times maintain said panel parallel thereto; spring means thatconstantly urge said panel forwardly from said frame means forpreventing said spring means from moving said panel forwardly beyond afirst vertical plane; a spring-loaded locking member pivotally supportedfrom said panel capable of removably engaging a portion of said frame tohold said panel in a second vertical plane when sufiicient pressure isapplied to said panel causing it to move thereto; a release memberoperatively associated with said locking member that releases said panelfrom said second plane position when pressure is applied to said panelto move it rearwardly therebeyond, and said spring means moving saidpanel forwardly from said released position when pres-' sure on saidpanel is removed; a horizontally disposed track; roller means mounted onsaid frame engaging said track; and guide means operatively associatedwith said frame that cooperate with said roller and track to maintainsaid frame in a fixed vertical plane.

8. A locking mechanism for a panel that is movably supported from aframe for lateral movement relative thereto and is at all times urgedforwardly from said frame by spring means which includes: a detent;means pivotally supporting said detent from said panel in a rearwardlydisposed position; a substantially L-shaped release member comprising arearwardly disposed extension having a curved concave lower edge and adownwardly and rearwardly extending first link; means pivotallysupporting said release member, from said detent; a second upwardly andrearwardly extending link; means pivotally supporting said second linkfrom said panel; means pivotally connecting the free ends of said firstandiigs second links; spring means that are at all times in tensionextending between said means pivotally supporting said release memberand said second link; and means mounted on said release member thatremovably engage a portion of said detent to prevent pivoting of saiddetent by said spring means below a predetermined elevation.

9. A locking mechanism for a panel that is movably supported from aframe for lateral movement relative thereto and is at all times urgedforwardly from said frame by spring means which includes: a detentformed with a seat capable of removably engaging and holding said framein a predetermined vertical plane; means pivotally supporting saiddetent from said panel in a rear- Wardly disposed position; asubstantially l..- shaped release member comprising a rearwardlydisposed extension having a curved concave lower edge and a downwardlyand rearwardly extending first link; means pivotally supporting saidrelease 65 member from said detent; a second upwardly and rearwardlyextending link; means pivotally supporting said second link from saidpanel; means pivotally connecting the free ends of said first and secondlinks; a roller rotatably supported on 70 said means pivotallyconnecting the free ends of said links; spring means that subject saidmeans pivotally supporting said release member and said second link toan inwardly directed force; and means mounted on said release memberthat re- 10 movably engage a portion of said detent to prevent pivotingof said detent by said spring means below a predetermined elevation.

10. A locking mechanism for a panel that is movably supported from aframe for lateral movement relative thereto and is at all times urgedforwardly from saidframe by spring means which includes: a detent formwith aseat capable of removably engaging and holding said frame in apredetermined vertical plane; means. pivotally supporting said detentfrom said panel in a rearwardly disposed position; a substantially L-shaped release member comprising a rearwardly disposed extension havinga curved concave lower edge and a downwardly and rearwardly extendingfirst link; means pivotally supporting said release memberfrom saiddetent; a second upwardly and rearwardly extending link; means pivotallysupporting said second link from said panel; means pivotally connectingthe free ends of said first and second links; spring means operativelyassociated with said detent and releasing member, said spring means atall times urging said detent into an engageable position with said framewhen said links are angularly and rearwardly disposed, and into anon-engageable position with said frame when said links are angularlyand forwardly disposed; and means operatively associated with saiddetent and releasing member that prevent said spring means pivoting saiddetent beyond a predetermined position.

11. A locking mechanism for a panel movably supported from a frame forlateral movement relative thereto which is at all times urged forwardlyfrom said frame by spring means which includes: a detent formed with aseat capable of removably engaging and holding said frame in apredetermined vertical'plane; means pivotally supporting said detentfrom said panel in a rearwardly disposed position; a substantially L-shaped release member comprising a rearwardly disposed extension havinga curved concave lower edge and a downwardly and rearwardly extendingfirst link; means pivotally supporting said release member from saiddetent; a second upwardly and rearwardly extending link; means vpivotally supporting 'said second link from said panel; meanspivotallyconnecting the free ends of said first and secondlinks; a helical springthat is at all times in tension extending between said means pivotallysupporting said release member and said second link, said spring at alltimes urging said detent into an engageable position with said framewhen said links are angularly and rearwardly disposed, and into anon-engageable position with said frame when said links are an gularlyand forwardly disposed; and an extension projecting from said releasemember that removably engages a portion of said detent to preventpivoting of said detent by said spring beyond a predetermined position.

12. A slidable door structure having two independently movable panels,comprising: a substantially rectangular framework including a header andsill joined by two longitudinally spaced uprights; two laterally spacedtrack members extending the length of said framework and disposed in theupper portion thereof substantially parallel to said header; asubstantially rectangular first panel; means 'to movably support saidfirst panel from the forwardly disposed of said tracks in a firstvertical plane; a substantially rectangular second panel; asubstantially rectangular frame disposed rearwardly of and parallel tosaid second panel; means to movably 11 support said second panel fromsaid frame; roller means that movably'support said frame from therearwardly disposed of said tracks; spring means that constantly urgesaid second panel forwardly from said frame to a position in saidfirstplane;

locking means operatively associated with said second panel and framethat removably maintains said second panel in said second verticalplane, said locking means when pressure is applied to said second paneldisposed in said second plane with sufficient force to move said second.panel rearwardly therefrom, being disengaged from said frame and movedforwardly by said spring means to a position in said first verticalplane, and said locking means when said second panel is moved rearwardlyfrom said first plane by the application of pressure, removably engagingsaid frame to maintain said second panel -in said second plane; andguide means cooperatively associated with said frame to maintainsaidframe in a 'fixed'ver'tical plane.

13. A slidable door structure having two independently movable panels,comprising: a substantially rectangular framework including a header andsill joined 'by two longitudinally spaced uprights; -two laterallyspaced track members extending the length of 'saidframework and disposedin the upper portion thereof substantially parallel to said header; asubstantially rectangular first panel; a substantially rectangularsecond panel; means to movably support said first panel from theforwardly disposed track in a first vertical plane; a substantiallyrectangular frame disposed rearwardly of "and parallel to said secondpanel; roller means that movably support said frame from the rearwardlydisposed track; spring means that constantly urge said second panelforwardly from said frame to a position insaid'first plane;spring-actuiatedlocking means that maintain said panel in a secondvertical plane -when sufficient pressure is applied to said second panelto cause it to move thereto; a releasing member operatively associatedwith said locking means thatreleases said panel from said second planeposition when pressure 'is applied to said panel to move it rearwardtherebeyond, and said spring means moving said panel forwardly from saidreleased position to said first plane position when pressure on saidpanel is removed; and guide means cooperatively associated with saidframe to maintain said frame in a fixed vertical plane,

14. A slidable door structure having two independently movable panels,comprising: a substantially rectangular framework including a header andsill joined by two longitudinally spaced uprights; two laterally spacedtrack members extending the length of said framework and disposed in theupper portion thereof substantially parallel to said header; asubstantially rectangular first panel; means to movably support saidfirst panel from the forwardly disposed track in-a first vertical plane;a substantially rectangular second panel; a substantially rectangularframe disposed rearwardly of and parallel to said second panel; rollermeans that movahly support said frame from the rearwardly disposedtrack; spring means that constantly urge said second panel forwardlyfrom said frame to a position in. said first plane; a spring-loadedlocking member pivotally supported from said second panel capable ofremovably engaging a portion of said frame to hold said second panel ina second vertical plane when sufficient pressure is applied to saidsecond panel to cause it to move thereto; a release member operativelyassociated with said locking member that releases said panel from saidsecond plane position when pressure is applied to said panel to move itrearwardly therebeyond, said spring means moving said panel forwardlyfrom said released position upon removal of said pressure; and guidemeans that cooperate with said frame to maintainsaid frame in a fixedvertical plane.

References Cited in the file of this patent UNZTED STATES PATENTS NumberName Date 841,378 Curtis Jan. 15, 1907 1596,1935 Marshall Aug. 24, 19261,724,438 Vance Aug. 13, 1929 1,937,978 Miller Dec. 5, 1933 2,547,319Harding Apr. 3, 1951 FOREIGN PATENTS Number Country Date 466,466GreatBritain May 28, 1937

